[n] the quality of moving freely
\Mo*bil"i*ty\, n. [L. mobilitas: cf. F. mobilit['e].]
1. The quality or state of being mobile; as, the mobility of a liquid, of an army, of the populace, of features, of a muscle. --Sir T. Browne.
2. The mob; the lower classes. [Humorous] --Dryden.